Drill boom with parallel motion linkage means



NOV.4, 1969 A.sTRoMNEs 3,476,193-

DRILL BOOM WITH PARALLEL MOTION LINKAGE MEANS Filed June 19, 1968 3Sheets-Sheet 1 INVENTOR. fli 5 m neg DRILL BOOM WITH PARALLEL MOTIONLINKAGE MEANS Filed June 19, 1968 Nov. 4, 1969 3 Sheets-$heet 2 Nov. 4,1969 A. STROMNES DRILL BOOM WITH PARALLEL MOTION LINKAGE MEANS FiledJune 19, 1968 3 Sheets-Sheet 5 I ll .36 48 Fig.8

United States Patent() 3,476,193 DRILL BOOM WITH PARALLEL MOTION LINKAGEMEANS Axel Stromnes, Tunabro, Sweden, assignor to Atlas CopcoAktiebolag, Nacka, Sweden, a corporation of Sweden Filed June 19, 1968,Ser. No. 738,240 Claims priority, application Sweden, June 22, 1967,

8,929/ 6 Int. Cl. E21c /08, 9/00, 11/00 US. Cl. 173-43 11 ClaimsABSTRACT OF THE DISCLOSURE The invention relates to drill booms for rockdrilling apparatus and more particularly to a drill boom arrangementwith parallel motion linkage means for positioning a rock drillingapparatus to a plurality of drilling positions all substantiallyparallel to one another. It is wellknown in the art in question todispose the parallel motion linkage along the entire length of the drillboom and to join it pivotally to the drilling apparatus near the pivotpoint thereof on the drill boom. In order to permit the choice of acompact construction, which is desirable due to the restricted workingspace of drill booms under ground, the supporting points of the feedshell are usually disposed close to each other which makes it difficultto attain sufficient stability of the feed shell under working thrustand torque in the various drilling positions thereof. An alternativescissors-like supporting of the feed shell by the aid of pivotallycrossed adjusting frames has therefore also been used for providing theparallel positioning. In this case the drilling apparatus is morerigidly supported but the space in front and below the feed shell isblocked by one of the scissors frames and the forward journal bearingthereof whereby the accessibility to the working face is reduced.

It is therefore the main object of the invention to provide a drill boomin which the feed shell is supported with increased rigidity by the aidof parallel linkage means and in which the linkage means are given sucha design that the space under the forward portions of the feed shell andthe drill boom are left free for easy access.

For these and other purposes there is according to the inventionprovided a drill boom arrangement with parallel motion linkage means forpositioning a rock drilling apparatus to a plurality of drillingpositions all substantially parallel to one another, said drill boomarrangement comprising a rock drilling apparatus, a boom support, adrill boom swingably mounted at the rear end thereof on said boomsupport, first pivot means on the forward end of said drill boom andconnected for supporting said rock drilling apparatus pivotally thereon,a supporting link piovtaly journalled on the intermediate portion ofsaid drill boom and extending rearwardly with respect to said drillboom, second pivot means on the rearward end of said supporting link andconnected for supporting said rock drilling apparatus pivotally thereon,means on one of said pivot means providing longitudinal movability ofsaid rock drilling apparatus relative to said ice one pivot means duringpivotal movement of said drill boom and supporting link, and a pilotlink pivotally journalled on said supporting link and on said boomsupport for providing substantially parallel displacement of said rockdrilling apparatus through the intermediary of said supporting link whensaid drill boom is pivoted relative to said boom support.

The above and other objects of the invention will become obvious fromthe following description and from the accompanying drawings in which apreferred embodiment of the invention is illustrated by way. of example.It should be undertsood that this embodiment is only illustrative of theinvention and that various modifications thereof may be made within thescope of the claims.

In the drawings FIG. 1 shows a side view of a drill boom arrangementaccording to the invention. FIG. 2 is a view on the line 2-2 in FIG. 1.The FIGURES 3a- 30 are views on the respective lines 3a3a, 3b--3b, and3c3c in FIG. 1. FIG. 4 shows a view partly in section on the line 44 inFIG. 1 through a mounting and turning means for the drill boom inFIG. 1. FIG. 5 is a detailed section on the line 55 in FIG. 3a. FIGS. 68are cross sections on the respective lines 66, 77, 88 in FIG. 1. FIG. 9,finally, is a detailed section on the line 9-9 in FIG. 1.

In the figures a drill boom 15 is journalled pivotally about an axle 16which is carried by a boom support 17. The drill boom 15 carries at itsunderside a pair of lugs 18 and a pivot 19. The boom support 17 carriesan axle 20 parallel with the axle 16. Between the axle 20' and the pivot19 is inserted a hydraulic cylinder and piston means or ram 21. Byextension or contraction of the hydraulic ram 21 the drill boom 15 maybe elevated or lowered with respect to the boom support 17.

The boom support 17 is screwed to an axle 23 disposed in the plane ofswing of the drill boom 15 which axle 23 is rotatably journalled in amounting also including a turning means 24, FIGS. 1, 4 intended forangular adjustment of the axle 23 within a wide angle for example of360. In the interior of the turning means 24 the axle 23 is providedwith a gear wheel 25 which is in engagement with two racks 27, 28 guidedfor reciprocation in cylinders 29, 30. The cylinders 29, 30 are suppliedwith pressure fluid at the opposite cylinder ends thereof via a controlvalve, not shown, for actuation of pistons 31 arranged at the oppositeends of the racks 27, 28. During turning of the axle 23 in one directionpressure fluid is supplied simultaneously to the lower end of thecylinder 29 and the upper end of the cylinder 30 while the opposite endsof these cylinders are relieved from pressure. During turning of theaxle 23 in the opposite direction pressure fluid supply takes place inthe opposite order to the lower end of the cylinder 30 and the upper endof the cylinder 29 while simultaneously therewith the opposite cylinderends are relieved.

The drill boom 15 carries a first pivot means or a pivot 33 at the outerend thereof on which a bracket 34 is pivotally journalled. The bracket34 includes two pairs of coaxial bearing sleeves 35 parallel to oneanother in which is slidably journalled a pair of guiding elementsprovided by two spaced guiding tubes 36 interconnected to form anelongated guiding frame. To the rear end of the guiding tubes 36 isaffixed second pivot means or a pair of pivots 37 on which a supportinglink 38 made as an elongated link frame is pivotally affixed. Thesupporting link 38 is double armed crossing the drill boom 15 and ispivotally journalled at the intermediate portion of the drill boom 15about side pivots 39. The length of the supporting link 38 between theside pivots 39 and the pivots 37 is chosen equal to the distance betweenthe side pivots 39 and the pivot 33 of the drill boom 15. The arm 40 ofthe supporting link 38 turned away from the pivot 37 is short and ispivotally journalled by means of pivots 41 to a pilot link 42. The pilot42 is fork shaped and the forked end thereof straddles the hydraulic ram21 and is pivotally journalled about the axle 20 of the boom support 17.

The guiding tubes 36 are part of a drilling apparatus carried by thedrill boom 15. Thus, on the guiding tubes 36 there is by means of a rearbracket 43 and a forward bracket 44 slidably guided a feed shell 45which in conventional manner carries a rock drill 46 thereon. The rockdrill 46 delivers blows to a drill steel 47 and is reciprocable on aslide along the feed shell 45 under the action of a feed motor, notshown. The rear bracket 43 of the feed shell 45 is affixed to ahydraulic cylinder and piston means or ram 48 FIGS. 30, and 9, thepiston rod 49 of which is affixed to the rear end of the guide element36 centrally between the pivots 37. The piston rod 49 consists of a tubewhich contains an inner tube 50 through which pressure fluid can besupplied to the working chamber in the hydraulic cylinder 48 turned awayfrom the piston rod therein. The space around the inner tube 50 in thepiston rod 49 can be supplied with pressure fluid through a lateralpassage 52 and communicates via laterally directed bores 53, FIG. 9,with the working chamber around the piston rod 49 in the hydrauliccylinder 48. By supply of pressure fluid to the inner tube 50 anddrawing off of pressure fluid via the passage 52 the feed shell 45 canbe displaced in forward direction along the guiding tubes 36 to restagainst the rock face to be drilled. Retraction of the feed shell 45 isperformed by supply and drawing otf of pressure fluid in the oppositeorder.

The feed shell 45 normally has to be placed horizontally in the variousdrilling positions thereof if the inclined positions for drilling roofand bottom holes are disregarded. To this end the pilot link 42 and thesupporting link 38 and the arm 40 thereof have been given such lengthsthat during elevation and lowering of the drill boom by means of thehydraulic ram 21 the guiding tubes 36 always will remain insubstantially horizontal position parallel to one another and to theaxle 23. The links 38, 42 are thus calculated to form parallel motionlinkage means for the feed shell 45 carried on the guiding tubes 36.

During drilling of inclined peripheral and bottom holes the feed hell 45must take a suitable angle with respect to the drilling positionsparallel to one another and to the axle 23. This angular setting isperformed by respective extension or contraction of the fork shapedpilot link 42, the shank portion of which incorporates two coaxialhydraulic rams with the cylinders 54, 55 thereof connected coaxially toone another. The piston rod 56 of the hydraulic cylinder 55 is connectedto axle via the forked portion of the pilot link 42. The piston rod 57of the hydraulic cylinder 54 is fixed to the pivots 41. The hydrauliccylinders 54, 55 are at the ends thereof provided with passages for thesupply or drawing off of pressure fluid and the pilot link 42 hasbetween the axle 20 and the pivots 41 the length necessary for paralleldisplacement of the feed shell when the hydraulic cylinder 54 is fullycontracted by its piston rod 57 taking its innermost position thereinsimultaneously with the piston rod 56 taking its maximally extendedposition from the hydraulic cylinder 55. This adjustment of the guidelinkage 42 is shown in FIG. 30. If in this position the piston rod 57 isextended maximally, the pilot link 42 will be extended whereby thesupporting link 38 is turned in the direction of the boom support 17 andthe pivots 37 of the guiding and tubes 36 are lowered. The rear end ofthe feed shell 45 is thus lowered to such an extent that a suitable roofhole angle is received for drilling of the roof hole. If, instead, inthe position shown in FIG. 30 the pilot link 48 is contracted bycontraction of the piston rod 56 into the cylinder 55, there will bereceived an elevation of the pivots 37 so that the rear end of the feedshell 45 is elevated and a suitable angle is set for drilling of forexample the bottom holes.

Obviously, by the arrangement of the parallel motion linkage meansshown, there is received compact construction paired with a rigidsupporting of the feed shell since the latter simultaneously getssupport near the forward as well as the rearward end thereof. Thisincreased rigidity facilitates interalia starting of a hole in anelfective manner. By the turning means 24 there is gained by the air ofthe drill boom 15 a considerable reach and large working area duringpositioning of the feed shell 45 to various drilling positions.

What I claim is:

1. A drill boom arrangement with parallel motion linkage means forpositioning a rock drilling apparatus to a plurality of drillingpositions all substantially parallel to one another, said drill boomarrangement comprising a rock drilling apparatus, a boom support, adrill boom swingably mounted at the rear end thereof on said boomsupport, first pivot means on the forward end of said drill boom andconnected for supporting said rock drilling apparatus pivotally thereon,a supporting link pivotally journalled on the intermediate portion ofsaid drill boom and extending rearwardly with respect to said drillboom, second pivot means on the rearward end of said supporting link andconnected for supporting said rock drilling apparatus pivotally thereon,means on one of said pivot means providing longitudinal movability ofsaid rock drilling apparatus relative to said one pivot means duringpivotal movement of said drill boom and supporting link, and a pilotlink pivotally journalled on said supporting link and on said boomsupport for providing substantially parallel displacement of said rockdrilling apparatus through the intermediary of said supporting link whensaid drill boom is pivoted relative to said boom support.

2. A drill boom arrangement according to claim 1 in which said meansproviding longitudinal movability of said rock drilling apparatusincludes guiding elements extending longitudinally thereof, and abracket pivotally carried by said first pivot means and supporting saidguiding elements and thereby said rock drilling apparatus longitudinallyslidably thereon, and in which aid second pivot means is connected tosaid rock drilling apparatus fixedly with respect to said guidingelements.

3. A drill boom arrangement according to claim 2 in which said rockdrilling apparatus includes an elongated feed shell and a rock drillslidably supported on said feed shell for reciprocal movement along saidfeed shell, and in which said guiding elements extend along said feedshell with said second pivot means connected to the rear end of saidguiding elements, bracket means supporting said feed shelllongitudinally slidably on said guiding elements, and hydraulic cylinderan piston means connected between said guiding elements and said feedshell for adjusting said feed shell longitudinally on and relative tosaid guiding elements.

4. A drill boom arrangement according to claim 1 in which saidsupporting link is a double-armed link frame pivoted to and crossingsaid intermediate portion of said drill boom, and in which said pilotlink is pivotally connected to the arm of said link frame opposite tosaid second pivot means.

5. A drill boom arrangement according to claim 1 in which said pilotlink includes hydraulic cylinder and piston means for respectivelyextension or contraction thereof and angular adjustment of said rockdrilling apparatus relative to the parallel drilling positions thereof.

6. A drill boom arrangement according to claim 5 in which said hydrauliccylinder and piston means consists of two hydraulic cylinders connectedto one another with the piston rod of one of them in operativeengagement with said supporting link and of the other with said boomsupport.

7. Drill boom arrangement according to claim 1 in which said boomsupport is carried rotatably on an axle parallel with said rock drillingapparatus in said parallel positions thereof, a mounting rotatablyreceiving said axle, and a turning means on said mounting includinghydraulic cylinder and piston means in engagement with said axle forselective angular adjustment thereof within a wide angle of the order ofmagnitude of 360.

8. A drill boom arrangement with parallel motion linkage means forpositioning a rock drilling apparatus to a plurality of drillingpositions all substantially parallel to one another, said drill boomarrangement comprising a rock drilling apparatus which includes anelongated feed shell, a rock drill slidably supported on said feed shellfor reciprocal movement along said feed shell, and an elongated guidingframe extending along and supporting said feed shell, a boom support, adrill boom swingably mounted at the rear end thereof on said boomsupport, first pivot means on the forward end of said drill boom, abracket pivotally carried by said first pivot means and supporting saidguiding frame and thereby said feed shell longitudinally slidably andpivotally relative to said drill boom, a supporting link frame pivotallyjournalled on the intermediate portion of said drill boom and extendingrearwardly with respect to said drill boom, second pivot means on therearward end of said supporting link frame connecting said supportingframe pivotally to the rear end of said guiding frame, and a pilot linkpivotally journalled on said supporting link and on said boom supportfor providing substantially parallel displacement of said guiding frameand feed shell through the intermediary of said supporting link whensaid drill boom is pivoted relative to said boom support.

9. A drill boom arrangement according to claim 8 in which saidsupporting link is a double-armed link frame pivoted to and crossingsaid intermediate portion of said drill boom, and in which said pilotlink is pivotally connected to the arm of said link frame opposite tosaid second pivot means.

10. A drill boom arrangement with parallel motion linkage means forpositioning a rock drilling apparatus to a plurality of drillingpositions all substantially parallel to one another, said drill boomarrangement comprising a mounting, an axle rotatably received in saidmounting, a turning means on said mounting including hydraulic cylinderand piston means in engagement with said axle for selective angularadjustment thereof, a boom support carried by said axle for rotationtherewith, a rock drilling apparatus, a drill boom swingably mounted atthe rear end thereof on said boom support in a plane including saidaxle, first pivot means on the forward end of said drill boom andconnected for supporting said rock drilling apparatus pivotally thereonin said plane, a supporting link pivotally journalled on theintermediate portion of said drill boom and extending rearwardly withrespect to said drill boom, second pivot means on the rearward end ofsaid supporting link and connected for supporting said rock drillingapparatus pivotally thereon in said plane and parallel with said axle,means on one of said pivot means providing longitudinal movability ofsaid rock drilling apparatus relative to said one pivot means duringpivotal movement of said drill boom and supporting link, and a pilotlink pivotally journalled on said supporting link and on said boomsupport for providing displacement of said rock drilling apparatussubstantially parallel with said axle through the intermediary of saidsupporting link when said drill boom is pivoted relative to said boomsupport.

11. A drill boom arrangement according to claim 10 in which said meansproviding longitudinal movability of said rock drilling apparatusincludes guiding elements extending longitudinally thereof, and abracket pivotally carried by said first pivot means and supporting saidguiding elements and thereby said rock drilling apparatus longitudinallyslidably thereon, and in which said second pivot means is connected tosaid rock drilling apparatus fixedly with respect to said guidingelements.

References Cited UNITED STATES PATENTS 2,614,807 10/ 1952 Curtis.3,295,800 1/1967 Quarnstrom et al. 173-43 X 3,306,374 2/1967 Stromnes173-43 3,399,734 9/1968 Folinbee 173-43 X ERNEST R. PURSER, PrimaryExaminer US. Cl. X.R.

